Kidney Week

Abstract: SA-OR042

Association of Dietary Magnesium (Mg2+) and Potassium (K+) Intake with Mortality and Kidney Failure in the CRIC Study

Session Information

• Exploring Dietary, Exercise, and Microbiome Interventions in CKD
  November 08, 2025 | Location: Room 360A, Convention Center
  Abstract Time: 05:20 PM - 05:30 PM

Category: Health Maintenance, Nutrition, and Metabolism

• 1500 Health Maintenance, Nutrition, and Metabolism

Authors

• Gillis, Margaret, Tufts Medical Center, Boston, Massachusetts, United States

Margaret Gillis, MD

• Tighiouart, Hocine, Tufts Medical Center, Boston, Massachusetts, United States

Hocine Tighiouart, MS

• Reaves, Allison Cook, Tufts Medical Center, Boston, Massachusetts, United States

Allison Cook Reaves, MD, MS

• Drew, David A., Tufts Medical Center, Boston, Massachusetts, United States

David A. Drew, MD, MS

Background

Increased intake of Mg²⁺ and K⁺ are each linked to lower risk of cardiovascular outcomes and death. While studies have shown improved kidney outcomes with increased dietary intake of Mg²⁺ or K⁺, data is limited in CKD patients.

Methods

Using Chronic Renal Insufficiency Cohort data, we included subjects with baseline dietary surveys and a follow up measure of eGFR (n = 3318). Estimated daily Mg²⁺ (including supplemental) and K⁺ intake were examined as predictors for subsequent death or kidney failure*. Our final statistical model^ was repeated and stratified into groups of eGFR < 30 and ≥ 30 ml/min.

Results

The median intake (mg/day) was 312 for Mg²⁺ and 2636 for K⁺. Higher Mg²⁺ and K⁺ intake were associated with a lower risk for death (Fig 1 a&c). Stratified analyses showed a similar relationship regardless of eGFR group (Fig 2 a&c). Mg²⁺ or K⁺ intake had no consistent relationship with kidney failure in the total cohort (Fig 1 b&d), but each appeared protective for kidney failure only in the eGFR ≥ 30 ml/min subgroup (Fig 2 b&d).

Conclusion

Our data suggest Mg²⁺ and K⁺ intake are protective against death in CKD patients, regardless of degree of kidney disease. While not statistically significant in all models, our data also suggest both Mg²⁺ and K⁺ intake may be protective against kidney failure, but only in those with an eGFR ≥ 30 ml/min. Future research should study the benefits or potential harms of Mg²⁺ and/or K⁺ supplementation in CKD patients.

Digital Object Identifier (DOI)

• doi: 10.1681/ASN.2025sn1prkee